Receiver



April 9, 1929. w, N, HUNTER 1,708,064

RECEIVER Filed Dec. 11., 1925 I N VEN TOR.

ATTORNEY;

Patented Apr. 9, 1929.

warren stares WILLIAM N. HUNTER, OF BLANCI'IESTER, OHIO.

RECEIVER.

Application filed December 11, 1935. Serial No. 74,829.

15 through the coils cause the diaphragm to vibrate and the diaphragm acting as a drum head produces sound waves. The fact that the transmitters and receivers are constructed on similar principles and operate, 20 one the reverse of the other, is well known and requires no further elaboration.

It is particularly my object to provide a vibratory diaphragm which will not be affected by chance vibrations of the instru- 25 ment itself which impair the clear tone of the sound waves and to this end it is my purpose to provide diaphragms comprising magnetic discs with mounting rings of shock absorbing material such as vulcanized rubber by which the discs may be held in proper position with relation to the cores the coils in the instrument, without the disc being clamped against any rigid parts of the instrument. It is further my object to vulcanize the mounting rings integrally with the discs so that the discs, and mounting rings may be provided as integral members.

Referring tothe drawing in which Ihave illustrated my invention as applied to a radio loud speaker:

Figure 1 is a plan view ofmy magnetic disc prior to its being vulcanized to the mounting members.

Figure 2 is a section throughone of the diaphragms ready for insertion into the receiver.

Figure 3 is a section of oneftype of receivershowing the diaphragm in operative position.

I have shown a magnetic disc 1 which has its outer periphery close to the edges perforated with holes 2. A rubber ring 3 having a peripheral slot 4 is then provided and the disc inserted into the slot.

The rubber is then vulcanized and flows within the holes 2, as indicated at 3 with a result that a diaphragm member is provided consisting of the central disc portion and the annular mounting members integrally vulcanized to the disc and so supporting the disc that the outer edges thereof are completely enclosed in the rubber. I have further found that a coating of beeswax 4: at the juncture of the ring 3 and the disc 1 seems to prevent the ring 3 from interfering with the free vibration of the disc 1 and to improve the vibratory tone of the disc. The receiver illustrated comprises the casing 5 within which the coils 6 are connected-with the wires 7. The casing has a central aperture 8 to allow'for the inser tion of a loud speaker horn and a downwardly flanged annular wall 9; preferably with internal threads for securing the cover 10 of the container within which the coils or diaphragm are mounted; The cover also has a central aperture 10 The receiver casing 11 has an adjustment thumb screw 12 which regulates the distance between the 'magnetic cores 13 and the diaphragm 1.

The diaphragm 1 supported by the annular ring 3 is disposed with the ring retained between the annular walls of the box and the inner side of the cover. The receiver casing has preferably external threads 14: which engage internal threads 15 of the cover member. By rotating the box within the cover anydesired clamping force may be obtained on the ring 3 to hold in position.

Although I have'shown a receiver with a single diaphragm, it should be understoodthat my invention does not relate to any particular type of receiver, but specifically relates to the mounting of the magnetic diaphragm and I consider the use of any shock absorbing material which is molded or vulcanized abouta magnetic disc so as to completely insulate the outer periphery of the disc from local vibrations, well within the range of mechanical equivalents.

Having thus described my invention, what- I claim as new and desire to secure by Let ters Patent, is

In a receiver, a recessed magnetic disc hav 5 ing an annular shock absorbing ring member enclosing said disc and integral por tions of said ring member extending'within said recesses to retain said disc in a complete shock resistant position, and a sealing coating of material formed over the pe'riplr eral juncture ofsaid disc and said enclosing ring member. 1 r

WILLIAM'N. HUNTER. 

